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Data Mining Principles (required for cw, useful for any project…) - a reminder (?). Based on Intro to Data Mining: CRISP-DM Prof Chris Clifton, Purdue Univ Thanks also to Laura Squier, SPSS for some of the material. Data Mining Process.
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Data Mining Principles (required for cw, useful for any project…)- a reminder (?) Based on Intro to Data Mining: CRISP-DM Prof Chris Clifton, Purdue Univ Thanks also to Laura Squier, SPSS for some of the material
Data Mining Process • Cross-Industry Standard Process for Data Mining (CRISP-DM) – a Methodology, not for Software Engineering, but data-analysis work • European Community funded effort to develop framework for data mining and text mining tasks • Goals: • Encourage interoperable tools across entire data mining process, by defining subtasks • Take the mystery/high-priced expertise out of simple data mining tasks – anyone can do it! (even students) CS490D
Why Should There be a Standard Process? • Framework for recording experience • Allows projects to be replicated, “real science” • Aid to project planning and management • “Comfort factor” for new adopters • Demonstrates maturity of Data Mining • Reduces dependency on “stars” The data mining process must be reliable and repeatable by people with little data mining background. CS490D
Why standardize the process? • CRoss Industry Standard Process for Data Mining • Initiative launched Sept.1996 • http://www.crisp-dm.org/ • SPSS/ISL, NCR, Daimler-Benz, OHRA • Funding from European commission • Over 200 members of the CRISP-DM SIG worldwide • DM Vendors - SPSS, NCR, IBM, SAS, SGI, Data Distilleries, Syllogic, Magnify, .. • System Suppliers / consultants - Cap Gemini, ICL Retail, Deloitte & Touche, … • End Users - BT, ABB, Lloyds Bank, AirTouch, Experian, ... • Linkedin.com groups: discussion, job adverts, … CS490D
CRISP-DM • Non-proprietary • Application/Industry neutral • Tool neutral • Focus on business issues and practical problems • As well as technical analysis • Framework for guidance • Experience base • Templates and case studies for guidance and analysis CS490D
CRISP-DM: Overview CS490D
CRISP-DM: Phases • Business Understanding • Understanding project objectives and requirements • Data mining problem definition • Data Understanding • Initial data collection and familiarization • Identify data quality issues • Initial, obvious results • Data Preparation • Record and attribute selection • Data cleansing • Modeling • Run the data analysis and data mining tools • Evaluation • Determine if results meet business objectives • Identify business issues that should have been addressed earlier • Deployment • Put the resulting models into practice • Set up for repeated/continuous mining of the data CS490D
Phases and Tasks/Reports Business Understanding Data Understanding Data Preparation Modeling Deployment Evaluation Determine Business Objectives Background Business Objectives Business Success Criteria Situation Assessment Inventory of Resources Requirements, Assumptions, and Constraints Risks and Contingencies Terminology Costs and Benefits Determine Data Mining Goal Data Mining Goals Data Mining Success Criteria Produce Project Plan Project PlanInitial Asessment of Tools and Techniques Collect Initial Data Initial Data Collection Report Describe Data Data Description Report Explore Data Data Exploration Report Verify Data Quality Data Quality Report Data Set Data Set Description Select Data Rationale for Inclusion / Exclusion Clean Data Data Cleaning Report Construct Data Derived Attributes Generated Records Integrate Data Merged Data Format Data Reformatted Data Select Modeling Technique Modeling Technique Modeling Assumptions Generate Test Design Test Design Build Model Parameter Settings Models Model Description Assess Model Model AssessmentRevised Parameter Settings Evaluate Results Assessment of Data Mining Results w.r.t. Business Success Criteria Approved Models Review Process Review of Process Determine Next Steps List of Possible Actions Decision Plan Deployment Deployment Plan Plan Monitoring and Maintenance Monitoring and Maintenance Plan Produce Final Report Final Report Final Presentation Review Project Experience Documentation CS490D
Business Understanding: Statement of Business Objective Statement of Data Mining objective Statement of Success Criteria Phases in the DM Process(1) CS490D
Business Understanding: Business Objective: attract Language academics to DM (to be our “customers”?) Data Mining objective: is domain English classed as UK or US English? (classify by salient features) Success Criteria: specific evidence: set of features which classify UK and US training data correctly, used to classify domain data-sets Phases in cw DM Process(1) CS490D
Data Understanding Collect data Describe data Explore the data Verify the quality and identify outliers Phases in the DM Process(2) CS490D
Data Understanding Select domain corpora to fit region covered by journal Describe texts: size, sources, markup, … Explore the texts – can you see any obvious indications they are UK/US? Verify the quality (are texts really from your domain? Errors? Repetitions?) and identify outliers (texts which don’t “belong”) Phases in cw DM Process(2) CS490D
Phases in the DM Process (3) Data preparation: • Can take over 90% of the time • Consolidation and Cleaning • table links, aggregation level, missing values, etc • Data selection • Remove “noisy” data, repetitions, etc • Remove outliers? • Select samples • visualization tools • Transformations - create new variables, formats CS490D
Phases in cw DM Process (3) Data preparation: • May take up to 90% of the time • Select Data • Rationale for Inclusion / Exclusion: if it isn‘t really from your domain – remove • Clean Data • Remove repetitions • Remove headers, footers, tables, pictures etc (BootCat does this automatically) • Transform Data • Convert to plain text (ditto) • Reduce to word-frequency list, keyword-freqs can be features in machine-learning CS490D
Phases in the DM Process(4) • Model building • Selection of the modeling techniques is based upon the data mining objective • Modeling can be an iterative process; may model for either description or prediction CS490D
Phases in cw DM Process(4) • Model building • Data Mining objective: is domain English classed as UK or US English? (classify by salient features) • “model” can be Decision Tree (or NN, or other classifier) based on freqs of UK-only terms and US-only terms (and sources used to derive these) • Data Visualization or On-Line Analytical Processing (OLAP) as well as Data Mining CS490D
Phases in the DM Process(5) • Model Evaluation • Evaluation of model: how well it performed, how well it met business needs • Methods and criteria depend on model type: • e.g., confusion matrix with classification models, mean error rate with regression models • Interpretation of model: important or not, easy or hard depends on algorithm CS490D
Phases in cw DM Process(5) • Model Evaluation • Evaluation of model: have you found and quantified key differences between UK, US English, to classify domain data? • Interpretation: don’t just present the results, try to explain possible reasons CS490D
Phases in the DM Process (6) • Deployment • Determine how the results need to be utilized • Who needs to use them? • How often do they need to be used • Deploy Data Mining results by: • Utilizing results as business rules • Publishing report for users, with recommendations to improve their business CS490D
Phases in cw DM Process (6) • Deployment • Produce a scientific report: Intro, Methods, Results, Conclusion; PowerPoint Movie Maker YouTube • Utilizing results as business rules: attract Language researchers to use text mining (as “customers” or collaborators for SoC researchers) CS490D
Why CRISP-DM? • The data mining process must be reliable and repeatable by people with little data mining skills (e.g. IT Consultants, students?...) • CRISP-DM provides a uniform framework for • guidelines • experience documentation • CRISP-DM is flexible to account for differences • Different business/agency problems • Different data CS490D
Why DM?: Concept Description • Descriptive vs. predictive data mining • Descriptive mining: describes concepts or task-relevant data sets in concise, summarative, informative, discriminative forms • Predictive mining: Based on data and analysis, constructs models from the data-set, and predicts the trend and properties of unknown data • Concept description: • Characterization: provides a concise and succinct summarization of the given collection of data • Comparison: provides descriptions comparing two or more collections of data
DM vs. OLAP • Data Mining: • can handle complex data types of the attributes and their aggregations • a more automated process • Online Analytic Processing (visualization): • restricted to a small number of dimension and measure types • user-controlled process CS490D
CRISP-DM: Summary • Business Understanding • Understanding project objectives and requirements • Data mining problem definition • Data Understanding • Initial data collection and familiarization • Identify data quality issues • Initial, obvious results • Data Preparation • Record and attribute selection • Data cleansing • Modeling • Run the data mining tools • Evaluation • Determine if results meet business objectives • Identify business issues that should have been addressed earlier • Deployment • Put the resulting models into practice • Set up for repeated/continuous mining of the data CS490D